一种新的土拨鼠α干扰素基因分型方法的建立及其意义

目的：建立新的土拨鼠α干扰素（IFN-α）基因分型方法，分析急性和慢性土拨鼠肝炎病毒（Woodchuck hepati-tis virus，WHV）感染的土拨鼠肝细胞中不同型别的IFN-α基因表达谱及其意义。方法：利用已知序列和基因型的土拨鼠IFN-α基因克隆质粒，建立基于土拨鼠IFN-α基因序列的限制性片段长度多态性的土拨鼠IFN-α基因分型方法。PolyIC体外刺激正常土拨鼠外周血单个核细胞（PBMC），调查正常土拨鼠PBMC受PolyIC刺激后IFN-α基因的表达谱。提取急性和慢性土拨鼠肝炎病毒感染的土拨鼠肝组织mRNA，RT-PCR扩增土拨鼠IFN-α基因，分子克隆后调查急性和慢性感染的土拨鼠肝细胞中IFN-α基因表达谱。结果：建立了土拨鼠IFN-α基因限制性片段长度多态性分型方法。急性和慢性感染的土拨鼠肝细胞中IFN-α基因的表达谱明显不同于正常动物的表达谱，假基因表达所占比例大。结论：新建立的土拨鼠IFN-α基因分型方法可用于分析土拨鼠不同组织中IFN-α的基因表达谱。     

Probe selection algorithm for oligonucleotide array-based medium-resolution genotyping

Medium-resolution genotyping has the goal of distinguishing different subgroups instead of each element in a group. An oligonucleotide array provides an inexpensive, high-throughput method to identify differences in DNA sequence among individuals, which is fundamental for genotyping. As the cost and difficulty of designing and fabricating the oligonucleotide array dramatically increase with the number of probes used, it is therefore important to have a design with a minimum number of probes meeting the requirement of medium-resolution genotyping. The first algorithm for designing and selecting probes for oligonucleotide array-based medium-resolution typing is reported. The goal in deriving the algorithm was to select a minimum number of probes from a large probe set on the premise of minimum loss of resolution. The algorithm, which was based on entropy, conditional entropy and mutual information theory, was used to select the minimum number of probes from a large probe set. The algorithm was tested on a human leukocyte antigen (HLA) sequence data set. Thirty probes were selected from 390 probes for HLA-A, and 60 probes were selected from 767 probes for HLA-B. Although the number of probes was reduced by almost ten times, the distinguishability was reduced only a little, by 0.45% (from 99.90% to 99.45%) for HLA-A and 0.27% (from 99.84% to 99.57%) for HLA-B, respectively. This is a satisfactory and practical result.     

THE POTENTIAL USES OF GENOTYPING OF PLASMODIUMFALCIPARUMISOLATESBYTHENESTEDPOLYMERASECHAINREACTION

巢式ＰＣＲ方法被应用于泰国疟区（Ｂｏｒａｉ）恶性疟原虫的基因分型。应用特异的等位基因引物扩增了恶性疟原虫裂殖子表面蛋白１（ＭＳＰ１）基因的１、４变异多态区。以凝胶电泳分析扩增的目的基因片段。结果表明：共分别检测出恶性疟原虫６个ＭＡＤ２０等位基因型、４个Ｋ１和１个ＲＯ３３等位基因型。在９个月的流行季节，上述虫株的等位基因频率没有明显的改变，关存在较高程度的恶性疟原虫不同等位基因株的混合感染。本文进一步阐明了巢式ＰＣＲ技术在疟疾流行病学上的应用前景及优点。     

Fetal RhD genotyping: A more efficient use of anti-D immunoglobulin

The most important application of blood group genotyping by molecular genetics is the prediction of fetal RhD phenotype in pregnant women with anti-D, in order to assess the risk of haemolytic disease of the fetus and newborn. This diagnostic test performed on cell-free fetal DNA in the maternal plasma, is now a routine procedure in some countries. High-throughput modifications of this form of fetal D-typing would be valuable for testing fetuses of all D-negative pregnant women to avoid unnecessary antenatal treatment with anti-D immunoglobulin in the 40% of D-negative pregnant women with a D-negative fetus. The results of trials in Bristol and Amsterdam suggest that such routine testing is feasible and accurate.     

ABO血型基因分型及应用

目的 :研究ABO血型基因分型的意义。方法 :采用聚合酶链反应 序列特异性引物 (PCR SSP)基因定型方法对ABO血型基因定型并观察其基因多态性分布特征和疑难血型检定。结果 :对已知ABO基因的DNA标本进行基因定型 ,证实文中的ABO基因定型方法可靠 ;对 10 4例健康、无血源关系的汉族个体ABO血型基因定型 ,结果与血清学所定表型完全符合 ;并用ABO基因分型技术解决临床输血前血型鉴定、产前胎儿血型鉴定、亲权试验及血清学亚型的正确性验证。结论 :ABO血型基因分型技术可以正确判定ABO血型疑难样本     

Mumps vaccine failure investigation in Novosibirsk, Russia, 2002–2004

The aims of this study were to estimate the importance of vaccine failure (VF) in cases of mumps during 2002-2004 in the city of Novosibirsk, Western Siberia, Russia, and to genotype the responsible virus strain. Mumps virus-specific RT-PCR testing of saliva was performed for 18 cases of mumps. Sera were tested for IgM and IgG, IgG avidity, and the ability to neutralise a panel of mumps viruses, including the Leningrad-3 mumps vaccine virus. Of the 12 patients for whom vaccination status was positively determined, 11 showed serological evidence of primary VF. Sequence analysis of virus RNA amplified from saliva revealed a genotype C2 virus in 2002, a genotype H2 virus in 2003, and both genotypes in 2004. Although several vaccinated patients were positive for mumps virus IgG at the time of first sampling, only nominal levels of neutralising antibody were detected, and these were effective in neutralising the vaccine strain, but not genotype C and H mumps virus strains. These results suggest that the majority of cases of mumps in vaccinees are caused by primary VF, defined as either a lack of seroconversion or a lack of IgG maturity, as based on avidity testing. The results also support the hypothesis that sera of low neutralising antibody titre have a limited ability to neutralise heterologous mumps virus strains, suggesting that antigenic differences between circulating and mumps vaccine virus strains may play a role in cases of breakthrough infection. Consistent with previous reports, mumps virus genotypes C and H continue to circulate in Novosibirsk.     

Human neutrophil antigen‐1, -3, -4, and -5 allele and genotype frequencies in the Croatian blood donor population and their clinical significance

ObjectivesHuman neutrophil antigens (HNAs) and antibodies play an important role in allo- and autoimmunity associated with immune neutropenia and transfusion reactions. The aim of this study was to determine the HNA-1, -3, -4 and -5 allele and genotype frequencies in the Croatian blood donor population to assess the role of HNA-1, -3, -4, and -5 alleles in the development of neonatal alloimmune neutropenia and antibody-mediated transfusion-related acute lung injury.Material and methodsA total of 371 blood samples from unselected healthy blood donors were analyzed. Samples from all 371 donors were genotyped for HNA-1, samples from 160 donors were genotyped for HNA-3, and samples from 142 donors were genotyped for HNA-4 and HNA-5 using the polymerase chain reaction with sequence-specific primers (PCR-SSP) method.ResultsThe frequencies of the FCGR3B*01, FCGR3B*02 and FCGR3B*03 HNA-1 alleles were 0.393, 0.607 and 0.022, and of the SLC44A2*01 and SLC44A2*02 HNA-3 alleles 0.781 and 0.219, respectively. The frequencies of the ITGAM*01 and ITGAM*02 HNA-4 alleles were 0.796 and 0.204, and of the ITGAL*01 and ITGAL*02 HNA-5 alleles 0.718 and 0.282, respectively.ConclusionThese are the first results on the HNA allele and genotype frequencies in the Croatian blood donor population. We observed no deviations from previous reports on Caucasian populations. Determination of the HNA antigen frequencies in the population is important to estimate the risk of alloimmunization to HNA, especially the risk of fetal-maternal incompatibility and alloantibody production by transfusion of the HNA incompatible blood components.     

青藏高原鼠疫耶尔森菌基因型分布

目的研究青藏高原鼠疫耶尔森菌（鼠疫菌）基因组型分布特征.方法对分离到的青藏高原鼠疫菌297株,根据已经证实的22个差异区段设计引物,每株鼠疫菌的每个基因差异区段都采用PCR技术进行验证.结果在喜马拉雅旱獭鼠疫自然疫源地中,鼠疫菌基因组型有9种,分别为1、5、6、7、8、10、11、新基因组型和Ype-ancestor型,其中以5、8和10型为主,3种基因组型合计所占比例为80.6%（204/253）,而且不同地区鼠疫菌基因组型的分布也不一致.青藏高原青海田鼠鼠疫疫源地鼠疫菌基因组型全部为14型.结论青藏高原鼠疫菌基因组型分布具有明显的地理特征.根据基因组型的分布状况推测出了鼠疫菌在青藏高原的传播路径.     

13个VNTR位点用于113株结核分支杆菌的基因分型研究

目的 应用数目可变串联重复序列（VNTR）分子分型技术，对北京地区113株肺结核临床分离菌株进行分型研究，探讨北京地区菌株DNA多态性和基因型特征。方法 采用PCR和琼脂糖凝胶电泳技术对结核分支杆菌13个VNTR位点进行检测，并应用Gel-Pro analyzer 3．1软件和BioNumerics3．0软件进行结果分析。结果 113株结核分支杆菌可分为4个基因型（分别为Ⅰ、Ⅱ、Ⅳ和Ⅴ型），其中Ⅰ型占92．0％（104/113），其他3型所占比例很小，分别为Ⅱ型占4．4％（5／113），Ⅳ和Ⅴ型均为1．8％（2／113），而标准菌株H37Rv在分型中为独立的一个基因型，即Ⅲ型。结论 北京地区的结核分支杆菌存在基因多态性，其主要流行型为Ⅰ型。     

人乳头瘤病毒基因分型芯片的建立及其在临床中的应用

目的 建立一种适合于临床应用的人乳头瘤病毒（HPV）基因分型检测新方法,并通过对宫颈分泌物标本检测,验证HPV基因分型检测新方法的临床使用效果.方法 利用HPV保守的L1区设计各型PCR扩增通用引物,根据GenBank中HPV的型特异性序列设计、合成分型探针,制备可对16、18、31、33、35、39、45、51、52、53、56、58、59、66和68型15种高危型和6、11和42型3种低危型HPV进行联合分型检测的膜芯片.通过对100例宫颈炎患者宫颈分泌物标本进行检测,以了解临床使用效果;对阳性标本进行测序以验证分型的准确性;对标准品进行测定以检测其灵敏度.结果 在100例临床样品中发现HPV感染病例30例,其中包括高危型中的HPV16、18、33、45、51、58和66,以及低危型中的HPV6、11和42,既有单一型感染也有混合型感染.灵敏度经标准品验证可达10个拷贝的HPV DNA分子.对单一类型感染基因测序分型证实,所建立的HPV基因芯片分型结果与测序结果完全一致.结论 利用PCR-膜芯片技术建立的HPV基因分型诊断方法可以简便、有效地检出所有已知的高危型和低危型HPV,并能明确其基因类型,适用于临床HPV感染的实验室诊断与流行病学研究.